Ophthalmic screening is essential for detection of diabetic retinopathy
Diabetes Canada recommends eye exams every 1–2 years upon diagnosis of type 2 diabetes.1 A systematic review found that an average of 175 (range 75–267) screening sessions are required to detect 1 case of sight-threatening diabetic retinopathy in patients without retinopathy at baseline.2
Teleretina screening is a viable adjunct to in-person screening
Teleretina screening involves digital transmission of ocular images obtained by a technician for remote evaluation by a specialist (Appendix 1, available at www.cmaj.ca/lookup/doi/10.1503/cmaj.202141/tab-related-content). Technicians typically require one-on-one training with a teleophthalmology expert to effectively capture images.3 High-level evidence shows > 95% sensitivity and specificity for detection of diabetic retinopathy using teleretina screening.1 Teleretina screening is associated with reduced costs relative to in-person assessment.3
Patients with diabetes are more likely to participate in remote screening than in-person visits
A recent meta-analysis found significantly greater patient attendance for teleretina screening compared with traditional in-person assessment (odds ratio 13.15, 95% confidence interval 8.01–21.61, p < 0.001).4 Patients in poor health with limited access to health care professionals have challenges attending in-person screening; these patients are a target demographic for teleretina assessment.1
Teleretina screening is not available or recommended for all patients
Current evidence-based guidelines for teleretina screening apply only to nonpregnant patients aged 12 years or older with type 2 diabetes.5 Occasionally, images obtained during telescreening may be deemed “ungradable,” requiring an in-person assessment.1 Conditions that may interfere with the digital photo acquisition include dense cataracts or corneal scars.6
Centralized teleretina referral systems are in development in Canada
Several teleretina clinics have been initiated across Canada.1 Primary care providers are encouraged to contact the Canadian Retina Society (www.crssrc.ca) for further information and guidance on referral to telescreening programs.
Footnotes
Competing interests: Jason Noble serves on the advisory board for Novartis and Bayer and is a speaker for Novartis. Varun Chaudhary has served on the advisory board and as a consultant for Novartis, Bayer and Roche, and has investigator-sponsored research grants and participates in clinical trials funded by Novartis, Bayer and Allergan. All of these competing interests are outside the submitted work. No other competing interests were declared.
This article has been peer reviewed.
References
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